全文获取类型
收费全文 | 5960篇 |
免费 | 1047篇 |
国内免费 | 588篇 |
专业分类
化学 | 3892篇 |
晶体学 | 59篇 |
力学 | 268篇 |
综合类 | 36篇 |
数学 | 772篇 |
物理学 | 2568篇 |
出版年
2024年 | 23篇 |
2023年 | 132篇 |
2022年 | 208篇 |
2021年 | 211篇 |
2020年 | 234篇 |
2019年 | 204篇 |
2018年 | 190篇 |
2017年 | 182篇 |
2016年 | 297篇 |
2015年 | 263篇 |
2014年 | 335篇 |
2013年 | 404篇 |
2012年 | 502篇 |
2011年 | 569篇 |
2010年 | 341篇 |
2009年 | 338篇 |
2008年 | 376篇 |
2007年 | 347篇 |
2006年 | 320篇 |
2005年 | 277篇 |
2004年 | 202篇 |
2003年 | 169篇 |
2002年 | 196篇 |
2001年 | 153篇 |
2000年 | 133篇 |
1999年 | 164篇 |
1998年 | 130篇 |
1997年 | 111篇 |
1996年 | 108篇 |
1995年 | 74篇 |
1994年 | 60篇 |
1993年 | 57篇 |
1992年 | 48篇 |
1991年 | 63篇 |
1990年 | 34篇 |
1989年 | 28篇 |
1988年 | 22篇 |
1987年 | 18篇 |
1986年 | 22篇 |
1985年 | 17篇 |
1984年 | 5篇 |
1983年 | 5篇 |
1982年 | 5篇 |
1981年 | 6篇 |
1980年 | 1篇 |
1979年 | 4篇 |
1978年 | 4篇 |
1977年 | 1篇 |
1976年 | 1篇 |
1957年 | 1篇 |
排序方式: 共有7595条查询结果,搜索用时 15 毫秒
991.
Dr. Karlee P. Castro Dr. Tyler T. Clikeman Nicholas J. DeWeerd Dr. Eric V. Bukovsky Kerry C. Rippy Dr. Igor V. Kuvychko Dr. Gao‐Lei Hou Dr. Yu‐Sheng Chen Dr. Xue‐Bin Wang Dr. Steven H. Strauss Dr. Olga V. Boltalina 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(12):3930-3936
In a simple, one‐step direct trifluoromethylation of phenazine with CF3I we prepared and characterized nine (poly)trifluoromethyl derivatives with up to six CF3 groups. The electrochemical reduction potentials and gas‐phase electron affinities show a direct, strict linear relation to the number of CF3 groups, with phenazine(CF3)6 reaching a record‐high electron affinity of 3.24 eV among perfluoroalkylated polyaromatics. 相似文献
992.
Wenhua Hou 《物理化学学报》2020,36(4):1912038-0
正与暴露非极性晶面的纳米材料相比,暴露极性面的纳米晶通常表现出不同寻常的性质~(1,2)。然而,极性晶面固有的偶极矩会导致表面结构出现多种变化~3,这对准确理解极性晶面结构并建立构效关系带来了巨大的挑战。当前研究晶面结构主要借助的是只能观测样品很小的一部分的电子显微镜技术,且该技术考察较轻的元素(如氢和氧)较为困难,因此亟须发展新的方法研究结构复杂的 相似文献
993.
Numerical Algorithms - In this paper, we present a second-order decoupled scheme based on the artificial compression method for the time-dependent Stokes-Darcy equations. This method not only... 相似文献
994.
Dr. Zhenbo Mo Dr. Takanori Shima Prof. Dr. Zhaomin Hou 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(22):8713-8722
Studies on N2 activation and transformation by transition metal hydride complexes are of particular interest and importance. The synthesis and diverse transformations of a dinitrogen dititanium hydride complex bearing the rigid acridane-based acriPNP-pincer ligands {[(acriPNP)Ti]2(μ2-η1:η2-N2)(μ2-H)2} are presented. This complex enabled N2 cleavage and hydrogenation even without additional H2 or other reducing agents. Furthermore, diverse transformations of the N2 unit with a variety of organometallic compounds such as ZnMe2, MgMe2, AlMe3, B(C6F5)3, PinBH, and PhSiH3 have been well established at the rigid acriPNP-ligated dititanium framework, such as reversible bonding-mode change between the end-on and side-on/end-on fashions, diborylative N=N bond cleavage, the formal insertion of two dimethylaluminum species into the N=N bond, and the formal insertion of two silylene units into the N=N bond. This work has revealed many unprecedented aspects of dinitrogen reaction chemistry. 相似文献
995.
Dr. Yong-Zhi Li Gang-Ding Wang Hong-Yun Yang Prof. Lei Hou Prof. Yao-Yu Wang Prof. Zhonghua Zhu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(69):16402-16407
To develop efficient adsorbent materials for storage and separation of C2H2, an unprecedented supercage MOF, [Me2NH2]⋅[Zn3(ALP)(TDC)2.5]⋅3.5DMF⋅2 H2O ( 1 ) was constructed through medicinal molecule allopurinol (ALP) and S-containing 2,5-thiophenedicarboxylic acid (H2TDC). 1 contains a novel linear trinuclear cluster that is composed by ALP and carboxylates and forms a final uncommon 5-connected yfy topological framework. The framework possesses three types of interlinked cages decorated by rich functional sites, and reveals not only high adsorption capacity for C2H2 but also excellent selective separation for C2H2/CO2 and C2H2/CH4 at 298 K. Dynamic breakthrough experiments on C2H2/CO2 (1:1) mixture and C2H2/CH4 (1:1) mixture also demonstrated the potential of the material to separate C2H2 from CO2 or CH4 mixtures. Molecular simulations were also studied to identify the different CO2- and C2H2- binding sites in 1 , such as carboxylate groups, S atoms and carbonyl groups. 相似文献
996.
997.
Progress in surface modification of magnetic nanoparticles(MNPs)is summarized with regard to organic molecules,macromolecules and inorganic materials.Many researchers are now devoted to synthesizing new types of multi-functional MNPs,which show great application potential in both diagnosis and treatment of disease.By employing an ever-greater variety of surface modification techniques,MNPs can satisfy more and more of the demands of medical practice in areas like magnetic resonance imaging(MRI),fluorescent marking,cell targeting,and drug delivery. 相似文献
998.
Hasna Kudilatt Bo Hou Mark E. Welland 《Particle & Particle Systems Characterization》2020,37(12):2000192
Colloidal quantum dots (QDs) have unique optical and electrical properties with promising applications in next-generation semiconductor technologies, including displays, lighting, solar cells, photodetectors, and image sensors. Advanced analytical tools to probe the optical, morphological, structural, compositional, and electrical properties of QDs and their ensemble solid films are of paramount importance for the understanding of their device performance. In this review, comprehensive studies on the state-of-the-art metrology approaches used in QD research are introduced, with particular focus on time-resolved (TR) and spatially resolved (SR) spectroscopy and microscopy. Through discussing these analysis techniques in different QD system, such as various compositions, sizes, and shell structures, the critical roles of these TR-spectroscopic and SR-microscopic techniques are highlighted, which provide the structural, morphological, compositional, optical, and electrical information to precisely design QDs and QD solid films. The employment of TR and SR analysis in integrated QD device systems is also discussed, which can offer detailed microstructural information for achieving high performance in specific applications. In the end, the current limitations of these analytical tools are discussed, and the future development of the possibility of interdisciplinary research in both QD fundamental and applied fields is prospected. 相似文献
999.
1000.